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Semidiscontinuous DNA replication

By: HWC, Views: 7337

During DNA replication, one of the two DNA strands, the leading strand, is replicated continuously, or all at once, in the 5' to 3' direction. The other strand, called the lagging strand, is replicated discontinuously, or in pieces, in the 3' to 5' direction. This is necessary because DNA poly...

Types of energy transfer reactions: oxidation-reduction reactions and ATP generation reactions

By: HWC, Views: 8264

■ Metabolism balances anabolic and catabolic reactions. ■ Anabolism is energy transfer from ATP to simpler molecules in order to build them up into larger, more complex molecules. ■ Catabolism is breaking down larger, more complex molecules, usually to transfer energy from them in order...

Magnetic resonance imaging (MRI)

By: Administrator, Views: 10796

Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body in both health and disease. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the or...

Definition of heart rate

By: HWC, Views: 7857

• Heart rate is determined by the rate of depolarizations of the sinoatrial (SA) node. • Cardiac output is directly proportional to heart rate, the greater the heart rate the greater the cardiac output. • Changes in heart rate are associated with exercise, stress or injury. Nervous ...

What are Strong & Weak Acids and How they're different?

By: HWC, Views: 6515

Let's consider the changes that take place when hydrogen chloride, HCI, is added to water. You will need to recognize space-filling models of HCI molecules, hydronium ions (H30+), chloride ions (C11, and water molecules (H20). They are shown at the right. When HC1 molecules dissolve in water, ...

Membrane transport proteins - pores, gated channels and pumps

By: HWC, Views: 7845

• a Three different types of membrane ion transport proteins are required to produce and carry electrical signals: • Pores • Gated channels • Na+/ K+ pump • Pores are always open and allow the diffusion of Na+ and K+ ions across the membrane, down their concentration gradients...

Miller's reaction chamber experiment Animation

By: HWC, Views: 1301

A simple diagram of Stanley Miller and Harold Urey's experimental apparatus. The lower portion of the apparatus was filled with water. The upper portion was filled with a mixture of gases that simulated the earth's early atmosphere. Examples are methane, ammonia, hydrogen and carbon dioxide. ...

The 4 steps of translation Animation

By: HWC, Views: 3548

Translation is the process of formation of a polypeptide chain according to codon present in mRNA. The four steps of translation are: Activation or charging of tRNA Initiation – recognition of start codon, binding of ribosomal subunits to mRNA and formation of initiation complex with Met-tR...

Protein catabolism (Krebs cycle) and Protein anabolism (protein synthesis)

By: HWC, Views: 8172

• Deaminated acids are brought into the Krebs cycle to be oxidized to CO2 and H2O. • Before entering the Krebs cycle, the deaminated acids are converted into intermediate products (pyruvic acid, acetyl coenzyme A, carbonic acids). • In the Krebs cycle, amino acids are oxidized to form r...